1 /* Copyright 2022 The TensorFlow Authors. All Rights Reserved. 2 3 Licensed under the Apache License, Version 2.0 (the "License"); 4 you may not use this file except in compliance with the License. 5 You may obtain a copy of the License at 6 7 http://www.apache.org/licenses/LICENSE-2.0 8 9 Unless required by applicable law or agreed to in writing, software 10 distributed under the License is distributed on an "AS IS" BASIS, 11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 See the License for the specific language governing permissions and 13 limitations under the License. 14 ==============================================================================*/ 15 16 #include "tensorflow/core/transforms/cse/pass.h" 17 18 #include <memory> 19 20 #include "mlir/IR/MLIRContext.h" // from @llvm-project 21 #include "mlir/Pass/Pass.h" // from @llvm-project 22 #include "mlir/Pass/PassManager.h" // from @llvm-project 23 #include "mlir/Support/LLVM.h" // from @llvm-project 24 #include "mlir/Support/TypeID.h" // from @llvm-project 25 #include "mlir/Transforms/Passes.h" // from @llvm-project 26 #include "tensorflow/core/ir/dialect.h" 27 #include "tensorflow/core/ir/ops.h" 28 #include "tensorflow/core/transforms/pass_detail.h" 29 30 namespace mlir { 31 namespace tfg { 32 namespace { 33 class CSEPass : public CSEPassBase<CSEPass> { 34 public: initialize(MLIRContext * context)35 LogicalResult initialize(MLIRContext *context) override { 36 dialect_ = context->getOrLoadDialect<TFGraphDialect>(); 37 return success(); 38 } 39 void runOnOperation() override; 40 41 private: 42 /// The cached TFG dialect instance. 43 TFGraphDialect *dialect_; 44 }; 45 } // namespace 46 runOnOperation()47void CSEPass::runOnOperation() { 48 GraphFuncOp func = getOperation(); 49 50 // Strip and save operation names. 51 DenseMap<Operation *, Attribute> op_names; 52 func.walk([&](Operation *op) { 53 if (Attribute name = op->removeAttr(dialect_->getNameAttrIdentifier())) { 54 op_names.insert({op, name}); 55 } 56 }); 57 58 // Run a nested CSE pass. 59 OpPassManager nested_manager(func->getName()); 60 nested_manager.addPass(createCSEPass()); 61 if (failed(runPipeline(nested_manager, func))) { 62 return signalPassFailure(); 63 } 64 65 // Re-assign names to any remaining operations. 66 func.walk([&](Operation *op) { 67 if (Attribute name = op_names.lookup(op)) { 68 op->setAttr(dialect_->getNameAttrIdentifier(), name); 69 } 70 }); 71 } 72 CreateCSEPass()73std::unique_ptr<Pass> CreateCSEPass() { return std::make_unique<CSEPass>(); } 74 } // namespace tfg 75 } // namespace mlir 76